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| What does the size of a wave dependent on? | The distance it travels, called its fetch, and the strength of the wind. |
| What are constructive waves? | Constructive waves build beaches. Each wave is low and it carries material up the beach in its swash. The beach material will then be deposited as the backwash soaks into the sand or slowly drains away. These waves are most common in summer. |
| What are the characteristics of Constructive waves? | They are low in proportion to their length, they have a strong swash and a weak backwash. |
| What are destructive waves? | Destructive waves destroy beaches. The waves are usually very high and very frequent. The back wash has less time to soak into the sand. As waves continue to hit the beach there is more running water to transport the material out to sea. These waves are most common in winter. |
| What are the characteristics of destructive waves? | They are high in proportion to their length, break downwards with great force, they have a weak swash and a strong backwash. |
| What are the four main processes which cause coastal erosion? | Abrasion, hydraulic action, attrition and corrosion. |
| What is abrasion? | Abrasion is when waves pick up beach material (e.g. pebbles) and hurl them at the base of a cliff. |
| What is hydraulic action? | When waves hit the base of a cliff air is compressed into cracks. When the wave retreats the air rushes out of the gap. Often this causes cliff material to break away. |
| What is Attrition? | Attrition is when waves cause rocks and pebbles to bump into each other and break up. |
| What is Corrosion? | Corrosion is when certain types of cliff erode as a result of weak acids in the sea. |
| What is Swash? | When a wave breaks and the water travels up the beach. Swash pushes sediment up the beach away from the sea. |
| What is Backwash? | When the water from the waves starts to run back down the beach. Backwash pulls beach material towards the sea. |
| What is Cliff Recession? | Erosion is greatest when waves break at the foot of a cliff. This causes erosion at the base of the cliff and creates a wave-cut notch in the base of the cliff. As the notch increases in size the weight of the cliffs above become too much and the cliff collapses. Where cliffs are made of more resistant material, wave cut platforms will be created. |
| What is a bay? | A body of water that is partly enclosed by land. |
| How does a bay form? | When soft rock erodes between areas of hard rock. |
| What is a headland? | A headland is an area of hard rock which sticks out into the sea. |
| How does a headland form? | Headlands form in areas of alternating hard and soft rock. Where the soft rock erodes bays are formed either side of the headland. |
| What are the stages of erosion of a headland? | First a cave is formed, eventually the cave erodes through the headland to form an arch, the roof of the arch then collapses leaving a column of rock called a stack and finally the stack collapses leaving a stump. |
| What is coastal deposition? | When the sea drops or deposits material. This can include sand, sediment and shingle. |
| What is a beach? | The beach is the area between the lowest and the highest tide levels. The lowest tide levels are reached during spring tides and the highest tides are the point reached by the storm waves.. They are usually made up of material deposited on a wave-cut platform. |
| What is longshore drift? | Longshore drift is the movement of material along the shore by wave action. It happens when waves moves towards the coast at an angle. The swash (waves moving up the beach) carries material up and along the beach. The backwash carries material back down the beach at right angles. This is the result of gravity. This process slowly moves material along the beach. Material in one place is eroded, transported then deposited elsewhere. |
| What is the main form of transportation along a beach? | Longshore drift. |
| What are the forms of transportation along a beach during longshore drift? | Traction, Saltation, Suspension, Solution. |
| What is Traction? | Large material is rolled along the sea floor. |
| What is Saltation? | Beach material is bounced along the sea floor. |
| What is Suspension? | Beach material is suspended and carried by the waves. |
| What is Solution? | Material is dissolved and carried by the water. |
